The present invention relates to a method and apparatus for determining photo-chemical reaction heat occurring when sensitive material reacts photo-chemically.
Applying high energy radiant rays such as light, to photo-sensitive material, such as photo-sensitive resin, causes a photo-chemical reaction such as photo-polymerization to be produced. At that time, exothermic or an endothermic reaction is generated. It is significant in determining optimum reaction conditions to determine the reaction heat produced during the photo-chemical reaction and furthermore to thereby determine the reaction velocity.
In the prior art, there has been used a calorimeter for determining the changes in fusing, transition, decomposition or the like which are caused when the temperature of certain material is raised for determining the thermal changes, such as exothermic or endothermic change, generated when different materials are mixed. However, in the prior art, there has not been such apparatus by which the exothermic or endothermic value may be determined when a certain material is added to a different material during the photo-chemical reaction under the above-mentioned fixed temperature.
In the above-mentioned determination, since the reaction velocity in photo-reaction differs or varies according to the temperature of the sample itself, it is required that the temperature of the surrounding atmosphere be maintained at a fixed value and that the temperature of the sample be maintained at a fixed one. However, even when the surrounding temperature is maintained constant, the temperature of the sample itself changes due to the reaction heat generated when the sample itself is reacted. Therefore, it becomes difficult to carry out the determination of the photo-chemical reaction heat with high accuracy.